The present invention relates to fiber reinforced thermoplastic materials.
The production of thermoplastic material of poly(arylene sulfide) resins reinforced with unidirectional glass fibers by pultrusion has been disclosed. See, for example, U.S. Pat. No. 4,680,224. At least one fiber strand of continuous filaments is contacted with a poly(arylene sulfide) resin in the form of a powder or a slurry. The impregnated strand or strands are then pulled through a temperature controlled die for producing a composite which can have the form of, for example, a tape, a rod or a sheet.
The glass fiber reinforced pre-preg tapes produced in this manner are useful for such applications as structural members, aircraft parts, doctor blades, and the like.
Aliphatic sulfide type silanes have been used in glass reinforced poly(phenylene sulfide) compositions to improve hydrolytic stability. These have not been used for continuous unidirectional fiber reinforced poly(phenylene sulfide) and do not address the object of improving transverse tensile properties in prepreg tapes.
For some applications the continuous fiber reinforced thermoplastic prepreg tape will be more useful with improved transverse tensile strength and improved hydrolytic stability. For example, doctor blades used to process aqueous-based materials require materials of construction that have good hydrolytic stability. Likewise, structural members subjected to multi-directional high loads require materials of construction with, among other properties, good transverse tensile strength. Good transverse tensile strength also avoids continuous fiber composite microcracking and mitigates the propagation of microcracking under loaded conditions.
It is known in the art to produce materials of woven glass fibers impregnated with poly(arylene sulfide) resins by means of lamination processes. These materials have been used for such applications as structural members and aircraft parts. These materials can also benefit from improved hydrolytic stability and from improved interply strength.